I wrap them up in a paper towel, put them into a zip lock bag and then snip the head off, cover with paper towel and close up the bag. It is fast and painless for the chick and you do not see much bad stuff.Please do not use the CO2 method. Using ether, also known as starting fluid, in a container is much more humane. The CO2 triggers a panic response because the body isn't getting oxygen. Ether simply knocks it out quickly and quietly. I've used it before on a chick with the same problem.